In this study, super-responders provided narratives on the range and time course of their response to biologic treatments. There is a lack of research in to patient perceptions of response to biologic treatments for severe asthma [19]. While previous qualitative research has collected data from patients on various add-on therapies [14, 20], this is the first study to focus on super-responders. The phrase “life-changing” and alternatives were frequently used by participants and their family/friends. This experience was characterised by reductions in asthma symptoms, chest infections, acute exacerbations and improved mental health. In many cases, participants described the elimination of daily symptoms, chest infections and exacerbations entirely. The participants in this study demonstrate that asthma remission [21] is a feasible treatment goal.
Compared to a recent study investigating predictors of response to Anti-IL5 drugs, participants in this present study had higher peak eosinophils in the previous 12 months and a higher exacerbation frequency [7]. Despite this, the participants in the present study described profound improvements to their quality of life following biologic treatment.
When describing the benefits of biologic treatments, participants focused on the physical improvements to their health. Most of the participants we interviewed described feeling benefit from their biologic after 2–3 months. Others reported benefits within as little as 2 days, or as long as 6 months, indicating that early response is not always the precursor of good response. This demonstrates that it may be possible to identify super-responders within 4 months of commencing a biologic treatment. Further quantitative research is needed to investigate the time course to improvements and identify for whom and when good response may be predicted.
Improvements to participants’ mental health took longer than improvements to their physical health. The persistence of anxiety despite the elimination of asthma symptoms is understandable and has also been observed in patients following cancer remission [22]. This finding, as well as the finding that there is great variability in the time it took to respond to a biologic, have implications for patient education before commencing a biologic.
Severe asthma can limit a person’s ability to engage in family life [13], including taking on childcare responsibilities [23], and concerns that they are a burden [24]. Participants in this present study described similar problems before commencing their biologic, but also how they reconnected with family once their symptoms decreased. This was noticed and appreciated by partners. The burden on family life is not assessed in clinical trials, which means the benefits of biologics on this aspect of patient’s lives is unappreciated. The impact of witnessing life-threatening attacks on their families, especially young children, were profound. Childhood stress is associated with poorer health in later life [25] and it is possible that witnessing a parent have asthma attacks leads to long term health consequences for a child. Further research is needed to investigate this and how improvement in a parent’s asthma benefits the family.
The range of benefits on quality of life reported were as wide as the range of different lives participants led and the aspirations they held. For one person it was to walk the coastal path, go surfing, or have a normal social life, for another to just be able to walk across a room without breathlessness. Participants were able to resume physical activity following biologic treatment and this was the second most important treatment outcome for people with severe asthma [11]. Exercise was often a social activity undertaken with friends or their partner, or while playing with their children. Participants thought of treatment success as being able to do the activities that mattered to them, rather than in terms of objective clinical improvement [26].
With respect to quantitative improvement there was an average increase in FEV1 of 100 ML on biologics from a baseline of 2.37L (79.4% predicted). This modest improvement does not reflect the profound improvement experienced by participants and highlights the discordance between lung function and quality of life. In contrast, two scores of quality of life (SAQ and SAQ-global) increased by 4 × and 3 × their respective MCID values, and better captured the experiences of participants.
The impact of biologics on patients’ lives merits further research. However, there is discordance between what is most important to people living with severe asthma and what is prioritised by clinicians [11, 26]. This is apparent from a clinician-led definition of super-responders [10]. If super-responders are identified using only objective clinical outcomes, data from this study suggests that many of the benefits of biologics treatments will be missed. Criteria for identifying super-responders must include Health-Related Quality of Life (HRQoL) if the wider benefits of biologics are to be captured. This also has implications for health economic evaluations which are often based on QALYs gained from a treatment.
Without a consensus definition, it is difficult to estimate the number of super-responders present in RCTs. Group mean data from trials may hide the participants who have life-transforming benefits. However, once a consensus definition is agreed, super-responders can be identified and sub-analyses of their data can be conducted. This will facilitate further research into predicting who will respond to which biologic. With the advent of personalised medicine [27] it becomes increasingly important to accurately measure the wider HRQoL benefit so that expensive resources are targeted to those with most to gain. It is clear that people with severe asthma and clinicians have different priorities for treatment goals yet at present the patient voice is not represented in discussions about them.
Limitations
The participants in this study were from a single centre and predominantly Caucasian. Further research is needed to determine if the results are consistent across different ethnicities and cultures. Due to the lack of consensus on the definition of a ‘super-responder’, participants were selected on the basis of an MDT decision after reviewing their patient-reported outcomes. Lastly, due to the time period that the interviews were conducted, some participants had been shielding during the Covid-19 pandemic. As such, it was difficult for them to say whether they had not developed a seasonal chest infection due to the biologics or because they were social distancing. Conversely, it was also not possible for some participants to take full advantage of their improved health due to shielding and anxiety related to COVID.